Chassis Battery at 11.5V

[jeffprupis]

Just identified this problem. While driving Inverter on drawing 20-40amps. Chassis batteries charging at only 11.5-8 volts. Turn on the geneset (while driving) house batteries charge at 10-12 amps. Chassis batteries charge at 12.2-6 volts. Coach seems to start fine after being hooked up to shore power. Am I looking at a chassis battery issue, alternator or something else? Thoughts please.

[Gerald Farris]

Jeff,
The first thing that I would do is check the engine alternator output. It sounds like you have a defective alternator. Also, from your description, it sounds like your inverter is set at a very reduced charging rate.

Gerald